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S60 Fuel Requirements S60 2003

I test drove an '03 S60 AWD and the Volvo dealer stated the car only requires regular gas. Is this true? Thanks

Giving my '95 965 with 301,000 mi and still running great to my best friend.








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    S60 Fuel Requirements S60 2003

    Reading all the posts here, it suggests that if the knock sensors detect knock then the ECU will immediately retard timing. That is not true. It takes miles/kms for the ECU to adapt to the lower octane-rate fuel. So, switching from high grade to low grade may cause some occasional pings (knocking) when going up hill (at high temperatures under heavy load).
    I have never noticed this with the window closed, but could here soemtimes with the window down.

    Also always using low-grade will effect in more audible pinging when under full load (window down again to hear) than in case of using always premium.
    However, occasionally pinging (under heavy acceleration, up hill etc) will do no harm: it is long-period pinging under normal driving conditions which will destroy the engine at the end.

    Switching form low to high grade will cause the opposite: it will take some time for the ECU to adjust before performance is improved.

    Personnally I only use the highest grade available, even with my NA S60 2001. Also this NA engine is adjusted close to knock to allow for best fuel economy!

    regards,

    Dutch








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      S60 Fuel Requirements S60 2003

      You know...these sensors in our cars are very sophisticated and I can tell an immediate difference between a tank of low octane and high octane gas as well as any possible knocking. If there is a knocking issue, our cars will set a code fairly quickly. So, I beg to differ with you that the immediate change of something such as fuel is detected slowly by our cars. If you stand by what you're saying I'll like to see the proof to back it up.
      --
      1998 S70 T5 Emarald Green Metallic (125K), 2004 V70 2.5T Ruby Red (45K), Previous Owner of Black '94 850 Turbo Wagon (Sold at 140K and miss her). My cars have been running so well lately they've got me worried.









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      'adjusted close to knock' ... Please, how did you do this?.... S60 2003

      re: "...Also this NA engine is adjusted close to knock to allow for best fuel economy!..."

      How did you do this? How is this done?

      I was under the impression that it's all (ignition timing, etc.) under control by the microprocessor -- you can't rotate the distributor to change timing or anything like that which we used to do with cars "in the old days".

      Forgive me if I'm wrong about these assumptions -- I really familiar with only 240s -- but my daughter just picked up her new '07 S60 2.5T this afternoon, and I'm trying to learn as much as I can about it -- even though I'm 3,000 miles away from her.

      Thanks.








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        'adjusted close to knock' ... Please, how did you do this?.... S60 2003

        Ignition timing is adjusted (for all fuel types) such that the engine will (just) not knock.

        Made-in-Jap: knock sensors are meant for adapting to octane rate: if the ECU would correct for every little ping identified by the knock sensors under heavy load, this would result in a severe performance degradation. Again: the ECU withh input from the knock sensors will adapt ignition timing to octane rate and that is done under normal driving conditions, not spefically under heavy load. Ignition timing variation etc for various driving conditions (flat vs laod)is set by the ECU with input from throttle position, rpm, etc.








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    And speaking of selecting AKI 91 fuel, the choices here are 89 or 93 - can't get 91 .... S60 2003

    It's actually curious that Volvo's engine would specify 91 octane (per my earlier message). Ninety-one is not available here.

    I don't know about the rest of the country, but here in New Jersey I notice that the Exxon station I go to offers 87, 89 and 93 octane gasoline. So if I had an S60, my choice would be to either choose 89 (and accept slightly sub-par performance, power and economy) or else to choose 93 and pay for slightly higher octane than I actually need.

    I was wondering if that's the dilemma in other parts of the country as well.








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      And speaking of selecting AKI 91 fuel, the choices here are 89 or 93 - can't get 91 .... S60 2003

      Volvo speaks with forked tongue on this issue, both in the owner's manual and at the dealer level. The owner's manual is jibberish - is it 91 or 87 - who could tell. At the dealer level salespeople tell you 87 but walk around the corner to service and they will tell you 91 is required. And they seem unembarassed about the duplicity. I wonder if Volvo made the owner's manual ambiguous on purpose. My experience is, and I don't drive hard, is that midgrade does not causing pinging or reduce fuel economy. I don't think this can be said about 87. If you drive more aggressively you will probably want 91.








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        Forked tongue? Not at all - it's quite clear and consistent. Let's read it together .... S60 2003

        re: "...Volvo speaks with forked tongue..., both in the owner's manual and at the dealer level.... At the dealer level salespeople tell you 87 but walk around the corner to service and they will tell you 91 is required. And they seem unembarassed about the duplicity...."

        I can't speak for what dealer you've been talking to -- sales people at your dealership are probably lying for the reason that they want to sell a car at a time when folks are concerned about gas prices and so they're promoting that it can use the cheapest gas. But who cares what sales people say?
        The manual, on the other hand, is quite consistent -- see next part for explanation. You've heard the saying, "read the manual -- no one knows your car better than the manufacturer that wrote the manual!", haven't you?

        re: "...The owner's manual is jibberish - is it 91 or 87 - who could tell...."

        You can tell, if you read it. Assuming you understand what a knock sensor is and what it does, then I have absolutely no idea why you're confused, what is confusing you, or what you're talking about. I'll explain the knock sensor below.

        But first, let's look at what the 2003's manual says, verbatim:

        On pg 78 of the 2003 owners manual, under "starting and driving", and then "...Fuel requirements", it reads:

        "....Octane rating
        Volvo engines are designed for optimum performance on unleaded premium gasoline with an AKI octane rating of 91 or above.... The minimum octane requirement is AKI 87 (RON 91)...."

        What's confusing about this? See the word "optimum"? See the word "minimum"? They mean different things.

        Here's where understanding a knock sensor comes into play. Volvo engines, since the early 1980's (B23s) have all had a knock sensor -- if the engine develops a ping (from too low an octane fuel when operating under a heavy load), the knock sensor detects the ping and sends a signal to the engine management system to lessen the advance so that the engine will stop pinging. However, this retardation of spark advance reduces power output as well as lowers fuel economy -- although the engine can run this way without damage.
        So, while the engine can run on a lower octane, i.e., AKI 87, this is a minimum (see that word?) octane and is not the best fuel for the engine. Presumeably, using lower than 87 fuel would induce more ping than the engine's management system can deal with.

        Now, the best fuel would be the octane at which no ping would occur under the heaviest load -- here, given the design of the engine it would be 91 octane fuel -- and the engine could realize its full potential of power and fuel economy with this fuel. Meaning that if you can find AKI 91 fuel, anything higher is unnecessary and a waste of money. So, AKI 91 is "optimum" (see that word again?) or best for the car as well as for your wallet.

        Bottom line: it can run on 87 or better without damage, but it will run better on higher octane fuels up to as high as 91. Greater than 91 is unnecessary.

        By the way, the manual also explains the AKI (ANTI KNOCK INDEX). Paraphrasing, AKI is the common rating system posted on gas pumps in the U.S.A. It is defined as (RON+MON)/2. So forget references in the manual for RON or MON (used in other countries -- remember that Volvo is an international corporation, and some folks operate their cars in other countries). In the U.S., you only need to know the AKI numbers.

        Hope this helped.








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      And speaking of selecting AKI 91 fuel, the choices here are 89 or 93 - can't get 91 .... S60 2003

      Same thing here...a pain, but a possilbe solution is to fill half up with 87 and the other half with 93, but that still gives you a 90 rating....LOL. Just fill up with the premium. You'll love it and your car will too.
      --
      1998 S70 T5 Emarald Green Metallic (125K), 2004 V70 2.5T Ruby Red (45K), Previous Owner of Black '94 850 Turbo Wagon (Sold at 140K and miss her). My cars have been running so well lately they've got me worried.








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    AKI 91 is optimal, while 87 is a 'desperation' minimum (per your owners manual) .... S60 2003

    I just looked up the owners manual for a '03 S60 on the web and found the following, quoted (copy-pasted) here:

    on pg 78, under "starting and driving", there is more extensive instructions, part of which which I've excerpted for you. Note that AKI (RON+MON/2) is the common rating system posted on gas pumps in the U.S.A.:

    "...Fuel requirements
    Octane rating
    Volvo engines are designed for optimum performance on unleaded premium gasoline with an AKI octane rating of 91 or above. AKI (ANTI KNOCK INDEX) is an average of the Research Octane Number, RON, and the Motor Octane Number, MON. (RON + MON/2). The minimum octane requirement is AKI 87 (RON 91)...."

    Bear in mind that the engine has a knock sensor. So in other words, the engine can be run on 87 -- although the engine's timing may be retarded when it's under load (if ping occurs), and this will diminish both power and fuel economy. On 91 octane, you'll get full performance under all conditions.

    Enjoy it.








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    S60 Fuel Requirements S60 2003

    In the back of the glove box manual, it lists the requirements of fuel type.
    Never believe a salesman!!!! Or a politician,

    Klaus
    --
    (V♂LV♂s 1995 854T, 1998 V70R)








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    S60 Fuel Requirements S60 2003

    If it's not a turbo, yes...if it's low pressure turbo, go at least mid-grade. If it has the hp turbo in it, then you better be running premium. Volvo dealers all say this thinking it's some king of incentive to buy a car or something.
    --
    1998 S70 T5 Emarald Green Metallic (125K), 2004 V70 2.5T Ruby Red (45K), Previous Owner of Black '94 850 Turbo Wagon (Sold at 140K and miss her). My cars have been running so well lately they've got me worried.







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